Stereo Tool

I'm still waiting for test ssb stereo...

New clipper does some tricks, I think I know how

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Urban Junglist

Me too! If I believe in the tests that the guys from Omnia did, this would be a big advantage for our station, as we have lot of multipath problems due to mountainous landscape in the southern of germany

I'm online again Saw Greenland from the air (wow!), walked around in Philadelphia and ate in Chinatown this afternoon and now I'm in Las Vegas, so I hope you understand that I won't be developing much this week

So, some answers:
1. Pilot and RDS are NOT clipped and should not be affected by the composite clipper
2. I also see that sometimes there's some 'noise' or something that causes some "dirt" in the spectrum. Not sure what it is yet, but it's definitely not intentional. First guess: The limiter doesn't limit enough at some point, causing the output to be slightly too loud and be 'hard clipped'. Not really something to worry about: The level is extremely low (around -80/-90 dB), so I think you'll never get reception that's good enough to be able to even measure it.
3. Unless I'm mistaking (I hope not), adding SSB should be very very simple now. I could probably do it in a few hours. Maybe on my flight back . Multicore support will be harder to add for this though... (So it's probably a good idea to add SSB first, to not get into trouble later).
4. I found a bug: Each time I run Stereo Tool (DSP plugin, so the audio/pilot/RDS should all start at the same point every time) with the composite clipper enabled, the output is different. That's bad. It doesn't happen with "Multicore" disabled! This may be related to a bug that Bojcha noticed: Sometimes the channels get swapped.

Ow i'm sorry than i must have misunderstood you. At least without hard limit it looks good so maybe that can be made better.

Definitely, but I need to figure out what's causing it first. For now, I wouldn't worry too much about it.

Edit: O - there are 2 things here.
One, some 'lobes' on the audio. THAT is intentional
Two, occasionally there's a 'flat line' - the whole spectrum contains a signal. That's an indication of (unprotected) clipping and that should never happen.

Yezzz! Can you tell something about the pricing for the composite clipper by now? And will it be possible to just license FM and CC without the declipper?

Anyway, have a great time at NAB and I'm glad to see some videos from your trip on your YouTube-Channel

I think that I remember seeing something like this occur when switching the composite clipper on or off but am not able to confirm right now as I'm not near the ST pc...

Your NAB trip sounds like it's been lots of fun so far!

I totally agree. The FM Stereo system less fragile than often believed. Some of the tricks I've done with the Orban 8100A/XT2 in past decades have thrown substantial trash into the pilot region (the mod monitor meter would jump up 2-3%) and yet the audio quality excelled. Fact is, I still have 3 of these systems running today & while they aren't as loud as ST, they sound great for 28 year old technology. Bottom line...if you can make your station sound good and remain legal, do it. The listener doesn't have a pilot monitor.

I think you're talking about this, right?
4 % Pilot Modulation, 40 dB Pilot Protection, and it still works
All is done in the analog domain, and it sounds freakin' awesome!

That's what I'm taking about. You'd also be amazed how little "damage" happens by opening the lowpass filter on ST to where the pilot loses it's protection. Not that there's any benefit to this but it further demonstrates that spending a lot of effort on keeping the pilot region pristine may not yield much benefit out here in the real world.